The situation gets worse when the soil temperature decreases
Nitrogen fertiliser comes in two formulations: ammonia-based and nitrate-based. To make the correct choice, you need to understand the difference.
When plants take up nitrate, they convert it to ammonia; for this reason, they more readily take up fertiliser in the ammonia form.
The problem, however, is that ammonia has a positive electrical charge, and is therefore magnetically attracted to (or ‘adsorbed’ onto) the negatively charged soil colloids. This means it is not in the soil solution, and hence is less accessible to plants.
One benefit of this is that, while attached to the soil colloids, ammonia cannot be leached by heavy rain or irrigation.
Of the nitrogenous fertilisers, ammonia (and ammonium sulphate in particular) has the greatest acidifying action on soil. This can be either good or bad; farmers with a high pH in their soils tend to find it an advantage.
This story is from the August 16, 2019 edition of Farmer's Weekly.
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This story is from the August 16, 2019 edition of Farmer's Weekly.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
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